The invention relates to an arrangement for a condenser microphone with a miniaturized accessory comprised of a housing with which an electrostatic transducer is connected, preferably replaceably.
In the recording of sound it is frequently necessary to keep the use of the microphone as inconspicuous as possible. This state of facts is taken into account, in the case of condenser microphones, by separating the transducer from the matching circuit, i.e., from the amplifier for the condenser microphone. It is already recognized that the transducer and the microphone amplifier, because of the high-impedance character of the transducer, should be kept as close to each other as possible. However, it may also be desired to alternatively employ a condenser microphone without separating such components from each other (compact mode); this presupposes that the removability of the transducer from the condenser-microphone amplifier is provided for in the actual construction of the microphone. This is always the case when transducers having different acoustical characteristics are to be interchangeably connectable to one and the same condenser-microphone amplifier. Such interchangeability is ever more in demand.
It is known to perform the separation of components using an intermediate metallic pipe through which run the connecting conductors for the separated components. Such pipe carries at its ends electrical contacts and mechanical connecting means. Because the construction is rigid, it is necessary, if different applications are foreseen, to keep available intermediate pipes of different lengths and having different configurations, e.g., bends. Additionally, there is the great disadvantage that the signal-to-noise ratio when the components are separated is inferior to the signal-to-noise ratio when the components are compactly arranged. This consideration, besides constituting a disadvantage in itself, in effect places limits upon the lengths of such pipes.
It is also known to so design the microphone that the removable transducer is united with certain circuit components of the microphone amplifier in such a manner that the combination of the transducer and such circuit components is connected to the rest of the microphone amplifier circuitry by means of connecting leads only after a transformation of the high output impedance of the transducer. In this way, a deterioration of the signal-to-noise ratio resulting upon separation of the transducer is avoided. However, in the alternative mode of use, i.e., in the compact arrangement, there will exist two electrical and mechanical dismantling points; besides the increased cost of such an expedient, there results additionally a decrease in overall operating reliability. Furthermore, the electrical connection extending from the transducer must be so designed as to be capable of being separated. As a result, larger dimensions become necessary for the separated module than would be required for a similar non-separable connection.